166 ON GROUSE DISEASE, ETC. 
intestinal contents of a tine healthy grouse, also sent from 
the same locality. In this case a very large number of the 
strongles occupied both caeca, though not in such prodigious 
numbers as in the emaciated bird above mentioned. There 
were several examples of the Tcenia linea —these tapeworms 
being limited to a narrow portion of the small intestine situ¬ 
ated from five to ten inches above the point of junction of the 
caeca with the large intestine. No other forms of entozoa 
were present. I may likewise add in this place that the 
more cursory examination of the contents of yet another 
grouse—the sixth under my observation from the same loca¬ 
lity—also yielded a quantity of strongles. A question will 
here naturally suggest itself to the mind of the practical man. 
Does not the fact of the occurrence of these parasites in the 
intestines of a so-called healthy grouse destroy the notion of 
disease from this source ? My reply is, f Certainly not.’ A 
large experience with the symptoms produced by entozoa, 
both in human and animal hearers, enables me to assert with 
confidence that the measure of feebleness, disease, or suffering 
usually corresponds with the degree of parasitism; hut not 
exclusively so, since another factor concerned in the welfare 
or destruction of the bearer, as the case may be, arises out of 
the constitutional vigour of the hearer. A strong bird will 
overcome or resist the irritation set up by the presence of 
hundreds of entozoa; while a feeble bird, or one attacked 
before it is perfectly grown, will more or less rapidly succumb 
to the invasion. It is the same with mankind. One person 
will have convulsions from a single parasite, whilst another 
will play the part of f host 9 or bearer to the same species of 
parasite without the slightest discomfort. On these and 
other grounds, therefore, with some reservation, I do not 
hesitate to express the opinion that the present grouse mur¬ 
rain may be due to parasites. The irritation, probable dis¬ 
tress, and subsequent emaciation of the birds are readily 
explained by the presence of hundreds and thousands of 
strongles ; and, as these parasites are very small, investigators 
seem to have hitherto overlooked them. I assume this to be 
the case, because I have neither encountered them previously, 
nor am I acquainted with any description corresponding with 
this species of parasite.” 
As the foregoing remarks comprise all the more essential 
facts originally communicated to The Field, I will now, before 
recording the results of further examinations, give a sys¬ 
tematic description of the new parasite. 
